关于CH57X蓝牙的初始化中SysTick_IRQn开关的疑问

/*******************************************************************************

 * @fn          CH57X_BLEInit

 *

 * [url=home.php?mod=space&uid=247401]@brief[/url]       BLE 库初始化

 *

 * input parameters

 *

 * @param       None.

 *

 * output parameters

 *

 * @param       None.

 *

 * [url=home.php?mod=space&uid=266161]@return[/url]      None.

 */

void CH57X_BLEInit( void )

{

  uint8 i;

  bleConfig_t cfg;

  if ( tmos_memcmp( VER_LIB, VER_FILE, strlen( VER_FILE ) ) == FALSE )

  {

    PRINT( "head file error...\n" );

    while( 1 )

      ;

  }

  SysTick_Config( SysTick_LOAD_RELOAD_Msk );

  PFIC_DisableIRQ( SysTick_IRQn );



  tmos_memset( &cfg, 0, sizeof(bleConfig_t) );

  cfg.MEMAddr = ( u32 ) MEM_BUF;

  cfg.MEMLen = ( u32 ) BLE_MEMHEAP_SIZE;

  cfg.BufMaxLen = ( u32 ) BLE_BUFF_MAX_LEN;

  cfg.BufNumber = ( u32 ) BLE_BUFF_NUM;

  cfg.TxNumEvent = ( u32 ) BLE_TX_NUM_EVENT;

  cfg.TxPower = ( u32 ) BLE_TX_POWER;

#if (defined (BLE_SNV)) && (BLE_SNV == TRUE)

  FLASH_ROM_LOCK( 0 );                    // 解锁flash

  cfg.SNVAddr = ( u32 ) BLE_SNV_ADDR;

  cfg.readFlashCB = Lib_Read_Flash;

  cfg.writeFlashCB = Lib_Write_Flash;

#endif

#if( CLK_OSC32K )        

  cfg.SelRTCClock = ( u32 ) CLK_OSC32K;

#endif

  cfg.ConnectNumber = ( PERIPHERAL_MAX_CONNECTION & 3 ) | ( CENTRAL_MAX_CONNECTION << 2 );

  cfg.srandCB = SYS_GetSysTickCnt;

#if (defined TEM_SAMPLE)  && (TEM_SAMPLE == TRUE)

  cfg.tsCB = HAL_GetInterTempValue;    // 根据温度变化校准RF和内部RC( 大于7摄氏度 )

#if( CLK_OSC32K )

  cfg.rcCB = Lib_Calibration_LSI;    // 内部32K时钟校准

#endif

#endif

#if (defined (HAL_SLEEP)) && (HAL_SLEEP == TRUE)

  cfg.WakeUpTime = WAKE_UP_RTC_MAX_TIME;

  cfg.sleepCB = CH57X_LowPower;    // 启用睡眠

#endif

#if (defined (BLE_MAC)) && (BLE_MAC == TRUE)

  for ( i = 0; i < 6; i++ )

    cfg.MacAddr[i] = MacAddr[5 - i];

#else

  {

    uint8 MacAddr[6];

    GetMACAddress( MacAddr );

    for(i=0;i<6;i++) cfg.MacAddr[i] = MacAddr[i];    // 使用芯片mac地址

  }

#endif

  if ( !cfg.MEMAddr || cfg.MEMLen < 4 * 1024 )

    while( 1 )

      ;

  i = BLE_LibInit( &cfg );

  if ( i )

  {

    PRINT( "LIB init error code: %x ...\n", i );

    while( 1 )

      ;

  }

}